Let Us Enhance Our Learning. Choose the correct option in each case. Class 7

Let Us Enhance Our Learning. Choose the correct option in each case. Class 7

Let Us Enhance Our Learning

Question 1.

Choose the correct option in each case. Class 7

(i) Your father bought a saucepan made of two different materials, A and B, as shown in Fig.. The materials A and B have the following properties:

(a) Both A and B are good conductors of heat

(b) Both A and B are poor conductors of heat

(c) A is a good conductor and B is a poor conductor of heat

(d) A is a poor conductor and B is a good conductor of heat

Answer:

(c) A is a good conductor and B is a poor conductor of heat

(ii) Pins are stuck to a metal strip with wax and a burning candle is kept below the rod, as shown in Fig.. Which of the following will happen?

(a) All the pins will fall almost at the same time

(b) Pins I and II will fall earlier than pins III and IV

(c) Pins I and II will fall later than pins III andlV .

(d) Pins II and III will fall almost at the same time

Answer:

(d) Pins II and III will fall almost at the same time

(iii) A smoke detector is a device that detects smoke and sounds an alarm. Suppose you are fitting a smoke detector in your room. The most suitable place for this device will be:

(a) Near the floor

(b) In the middle of a wall

(c) On the ceiling

(d) Anywhere in the room

Answer:

(c) On the ceiling